2009-05-19 09:44:38
Excessive cola consumption can lead to anything from mild weakness to profound
muscle paralysis, doctors are warning.
This is because the drink can cause blood potassium to drop dangerously low,
they report in the International Journal of Clinical Practice.
They tell of the curious case of an Australian ostrich farmer who needed
emergency care for lung paralysis after drinking 4-10 litres of cola a day.
He made a full recovery and was advised to curtail his cola drinking.
We have every reason to think that it is not rare
Dr Clifford Packer from the Louis Stokes Cleveland VA Medical Centre in Ohio
Another example included a pregnant woman who regularly consumed up to three
litres a day for the last six years and complained of tiredness, appetite loss
and persistent vomiting.
A heart trace revealed she had an irregular heartbeat, most likely caused by
her low blood potassium levels.
Once she stopped drinking so much cola, she made a full and uneventful
recovery.
The investigators believe these cases are not atypical and that many people
risk problems due to their intake.
Moderate consumption of cola drinks is completely safe and people can
continue to enjoy such drinks as part of a balanced diet and active lifestyle
A spokeswoman from the British Soft Drinks Association
Manufacturers insist the products are safe when consumed in moderation.
In a commentary, Dr Clifford Packer from the Louis Stokes Cleveland VA Medical
Centre in Ohio said: "We have every reason to think that it is not rare.
"With aggressive mass marketing, super-sizing of soft drinks, and the effects
of caffeine tolerance and dependence, there is very little doubt that tens of
millions of people in industrialised countries drink at least 2-3 l of cola per
day.
"It follows that the serum potassium levels of these heavy cola drinkers are
dropping, in some cases, to dangerous low levels."
Moderation
The author of the research paper, Dr Moses Elisaf from the University of
Ioannina in Greece, said it appeared that hypokalaemia can be caused by
excessive consumption of three of the most common ingredients in cola drinks -
glucose, fructose and caffeine.
"The individual role of each of these ingredients in the pathophysiology of
cola-induced hypokalaemia has not been determined and may vary in different
patients.
"However in most of the cases we looked at for our review, caffeine
intoxication was thought to play the most important role.
"This has been borne out by case studies that focus on other products that
contain high levels of caffeine but no glucose or fructose."
Despite this, he warned that caffeine free cola products could also cause
hypokalaemia because the fructose they contain can cause diarrhoea.
"We believe that further studies are needed to establish how much is too much
when it comes to the daily consumption of cola drinks."
Excessive consumption has already been linked with obesity, diabetes and tooth
and bone problems.
A spokeswoman from the British Soft Drinks Association said: "The examples used
in this paper by the IJCP are all very extreme cases - moderate consumption of
cola drinks is completely safe and people can continue to enjoy such drinks as
part of a balanced diet and active lifestyle.
"The soft drinks industry is committed to encouraging responsible consumption
of all its products. Nutrition labelling is included on pack so people can make
an informed choice about the products they are drinking."